1. Field of the Invention
The present invention relates to an electronic component in which a substrate and a lid member are joined to each other via a frame-shaped supporting body including a heat-curable resin, and relates to a manufacturing method therefor.
2. Description of the Related Art
In a surface acoustic wave filter device, for example, a package structure having a cavity is adopted, in which a surface acoustic wave filter element faces the cavity. Consequently, in order to make progress in size reduction of such a device, development of wafer level chip size packaging (WLCSP) has been progressing. In WLCSP, the size of the planar shape of a package is the same as that of a surface acoustic wave element chip.
For example, in Japanese Unexamined Patent Application Publication No. 2002-532934, an example of this kind of surface acoustic wave device is disclosed. As illustrated in FIG. 9, a surface acoustic wave device 1001 described in Japanese Unexamined Patent Application Publication No. 2002-532934 includes a plate-shaped surface acoustic wave element 1002. The surface acoustic wave element 1002 includes a piezoelectric substrate 1003. Functional units 1004 including interdigital transducer (IDT), electrodes are formed on the upper surface of the piezoelectric substrate 1003. A rectangular frame-shaped supporting body 1005 is formed on the upper surface of the surface acoustic wave element 1002. The supporting body 1005 is arranged so as to surround the functional units 1004. A lid member 1006 is fixed to the top of the supporting body 1005 such that a cavity that the functional units 1004 face is sealed.
Penetrating electrodes 1007 are formed so as to penetrate through the frame-shaped supporting body 1005 and the lid member 1006. Outer terminals 1008 are formed on the upper ends of the penetrating electrodes 1007.
In the surface acoustic wave device 1001, the outer peripheries of the supporting body 1005 and the lid member 1006 have the same dimensions as the outer periphery of the surface acoustic wave element 1002. Therefore, a reduction in size can be achieved.
On the other hand, in the surface acoustic wave device 1001, the wider the cavity which the functional units 1004 face becomes, the greater the number of functional units that can be arranged in the cavity. If the size of the cavity can be increased, size reduction of the surface acoustic wave device 1001 can also progress. In order to increase the area of the planar shape of the cavity, the width of the frame-shaped supporting body 1005 may be decreased. However, the frame-shaped supporting body 1005 needs to have a certain width in order to allow the penetrating electrodes 1007 to be formed. In this case, the area of the cavity is decreased. In addition, if the width of the supporting body 1005 is decreased, the cavity cannot be sufficiently tightly sealed. Accordingly, in cases such as where there is a change in temperature, there is a risk of leak defects occurring. Consequently, there has been a problem in that the environmental resistance has been degraded.